Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

Explain about the colorimeter, Explain about the Colorimeter? Colorimet...

Explain about the Colorimeter? Colorimeter is an instrument for measuring the colour or colour intensity of a solution. It is an instrument that measures the concentration of a

Explain the soft diet, Explain the soft diet The soft diet provides so...

Explain the soft diet The soft diet provides soft whole food that is lightly seasoned and moderately low in fibre. The foods have a soft  texture and are easy  to digest. Smal

What is recombination frequency, What is recombination frequency? Recom...

What is recombination frequency? Recombination frequency, or crossing over rate, is the percentage of recombinant gametes made by crossing over (in relation to the number of pa

Define iron status of the individual, Define Iron Status of the Individual ...

Define Iron Status of the Individual Lastly, iron status of the individual is a floury determinant of how much iron is absorbed. On a mixed diet with some haem iron, the overal

Describe paradoxical and reverse split s in second heart, Describe Paradoxi...

Describe Paradoxical and Reverse Split S in second heart sound? Sequence of seminar valve closure reversed i.e. P, proceeds A. A reversed split is nearly always due to delayed

Name some emulsifiers which are present in nature, Name some emulsifiers wh...

Name some emulsifiers which are present in nature? There are many emulsifiers which are present in nature such as phospholipids e.g. lectin which is present in egg yolk which a

AP Biology, Explain the difference between endoparasite, ecctoparasite, and...

Explain the difference between endoparasite, ecctoparasite, and parasitoidism

Nocardiosis, Nocardiosis Nocardiae are aerobic, saprophytic, gram-posi...

Nocardiosis Nocardiae are aerobic, saprophytic, gram-positive, partially acid-fast filamentous bacteria. Currently, there are 30 species included within the genus. Members of

What do you mean by the notochord, Q. What is the notochord? How is this st...

Q. What is the notochord? How is this structure formed? The notochord is a rodlike structure that outlines the supporting axis of the embryo and gives birth to the vertebral co

Explain what is periodontal condition, Explain what is Periodontal Conditio...

Explain what is Periodontal Condition? If intact attachment apperatus without pocket, time is critical direction toward non-surgical repair to prevent periodontal breakdown

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd